For decades, the international fishing industry has been concerned with the problems of separating undesired marine items from the more desirable catch-items.
For example, shrimp trawling operations have been plagued for years with problems involving the entrainment of trash, undesired large fish, and undesired small fish in the marine-catch container, i.e. the net-like bag referred to as the "cod-end" of trawling gear.
The entrainment of undesired large and small fish and trash in the catch bag tends to cause undesired crushing and bruising of the desirable, intermediate size shrimp, causes the trawler operator to haul the trawling gear at more frequent intervals than would be desired, and significantly reduces the amount of usable catch retrieved during any trawling operation. Such entrainment also results in the needless destruction of larger and smaller marien life.
Over the years, a variety of approaches have been employed by the fishing industry in an effort to properly and effectively segregate or handle marine catches. Representative of such prior art efforts are the following:
(1) Fish Classifiers Utilizing Trawler Nets With Sieves and "Spiller" Outlets for Trash, Etc. PA0 (2) Miscellaneous Trash Ejectors or Spillers PA0 (3) Fish Classifying Sieves Invorporated in Trawler Nets PA0 (4) Trawler Nets with Conduits Leading to Tow-Boat PA0 (5) Miscellaneous Fish Sorting and/or Classifying and/or Escape Devices
U.S. Pat. No. 3,015,903 PA2 U.S. Pat. No. 3,440,752 PA2 French Pat. No. 1,442,545 PA2 U.S. Pat. No. 3,132,434 PA2 U.S. Pat. No. 3,195,261 PA2 U.S. Pat. No. 4,043,068 PA2 British Pat. No. 405,405 PA2 Canadian Pat. No. 714,269 PA2 Canadian Pat. No. 729,367 PA2 U.S. Pat. No. 589,047 PA2 U.S. Pat. No. 1,745,251 PA2 U.S. Pat. No. 2,618,879 PA2 U.S. Pat. No. 2,948,980 PA2 Canadian Pat. No. 609,882 PA2 U.S. Pat. No. 1,447,553 PA2 U.S. Pat. No. 1,462,196 PA2 U.S. Pat. No. 2,056,772 PA2 U.S. Pat. No. 3,849,927 PA2 U.S. Pat. No. 4,006,549 PA2 U.S. Pat. No. 4,174,582 PA2 U.S. Pat. No. 4,193,219 PA2 "New Dutch Beam Trawl Stops Flatfish Slaughter", World Fishing, June 1965, pages 96 and 99. PA2 "U.S. Design for `Separator` Shrimp Trawl", World Fishing, June, 2969, pages 60-62. PA2 reduce the amount of marine items flowing toward the said marine-catch container means, and PA2 increase the average size of marine items flowing toward the marine-catch container means; and
The long period of time span by these prior art efforts evidences the continuing nature of the problems associated with attempting to effectively classify or size-sort marine catches so as to improve the efficiency of fishing operations, reduce the amount of trawling sequences (and fuel required) in order to obtain a particular usable catch load, and prevent the needless entrapment and killing of large or small size fish or marine life.
Accordingly, the present invention is directed toward a unique approach for classifying marine items, particularly in relation to trawling operations, by segregating relatively larger sized and relatively smaller sized marine items from a flow of water and marine items, before this flow is entrapped within a marine catch container means such as the "cod-end" of trawling gear.
In accomplishing this objective, the present invention entails various independently significant method and apparatus aspects as follows:
While each aspect will be individually described in a method context, it will be recognized that the claims appended hereto present independently significant method facets of the invention, alone and in combination, as well as apparatus counterparts thereof.
In one aspect a method is presented for classifying marine items in an underwater environment which method utilizes
floating vessel means; PA1 marine-catch container means having marine item receiving entrance means; and PA1 operating means interconnecting the floating vessel means and the marine-catch container means and operable, in response to movement of the floating vessel means, to induce marine-catch entrapping movement of the marine-catch container means. PA1 separating relatively smaller marine items under water from a flow of marine items and water entering the entrance means of the marine-catch container means; and PA1 discharging the separated, relatively smaller marine items generally transversely of the marine-catch container means prior to the flowing of the remainder of the marine items into the entrance of the marine catch container means; PA1 the separating and discharging of the relatively smaller marine items being generally operable to PA1 the separating of the relatively smaller marine items being operable to retain marine items, generally larger than the separated relatively smaller marine items, in the flow of marine items and water entering the entrance means. PA1 providing baffle means positioned generally upstream of the entrance means of the marine-catch container means, with this baffle means being operable to reduce the flow rate of water entering the entrance means of the marine catch container means so as to increase the degree of dispersion of the marine-catch therewithin. PA1 a plurality of flexible and yieldable barriers extending generally longitudinally of the flow direction of said marine items flowing toward said marine-catch container means and operable to yieldably deflect, generally laterally outwardly upstream of the entrance means of the marine-catch container means, so as to permit discharging of said relatively smaller marine-catch items; and PA1 means operable to tend to equalize water pressure generally transversely across the flexible and yieldable barriers. PA1 reduce the flow rate of water carrying the marine items; and PA1 reduce the flow pressure of water acting on the marine items after the separating of the relatively smaller marine items. PA1 reduce the number of items flowing toward the marine-catch container means, and PA1 decrease the average size of marine items flowing toward the marine-catch container means. PA1 a plurality of flexible and yieldable barriers extending generally longitudinally of the flow direction of marine items flowing toward the marine-catch container means and operable to yieldably deflect generally laterally outwardly to permit the discharge of the relatively larger marine items, and PA1 means operable to tend to equalize water pressure transversely across this plurality of flexible and yieldable barriers included in the additional wall means. PA1 reduce the flow of water carrying marine items, and PA1 reduce the flow of water acting on the marine items during the separating of the relatively larger marine items. PA1 reduce the number of items flowing toward the marine-catch container means, and PA1 decrease the average size of marine items flowing toward the marine-catch container means. PA1 permit desired marine catch items to flow therebetween toward the marine-catch container means, and PA1 transversely deflect, without impedance, or gravitational deterrence, these relatively larger marine items. PA1 generally freely yieldable barrier means extending generally longitudinally of the flow direction of marine items flowing toward the marine-catch container means and operable to yield generally outwardly to permit the discharging of the relatively larger marine items. The wall means is positioned inwardly of the outer extremeties of the generally smooth, parallel, and straight rod surfaces to permit generally free longitudinal flow of water on opposite sides of the wall means.
This method is characterized by the improvement comprising:
Another method aspect entails the baffling of the flow of marine items and water flowing toward the marine-catch container means by
A further method aspect relates to the providing of multiple segment, flexible wall means yieldably impeding the flow of marine items and water into the marine-catch container means, with this flexible wall means providing
Still another method aspect pertains to providing expansion chamber means operable to permit the expansion of a flow of water containing marine items flowing toward the marine-catch container means, after the separating and discharging of the relatively smaller marine items. This expansion chamber means is operable to
Yet another method aspect involves the separating of relatively larger marine items from a flow of marine items flowing generally towards the marine-catch container means, prior to the separating and discharging of the relatively smaller marine items, and the discharging of the separated generally larger marine items, generally laterally of the marine-catch container means. This separating and discharging of the relatively larger marine items is operable to
In a further method aspect, there are provided additional, multiple segment, flexible and yieldable wall means yieldably impeding the discharging of marine items and comprising
Moreover, a method aspect is contemplated wherein additional expansion chamber means are provided so as to be operable to permit the expansion of a flow of water containing marine items flowing toward the marine-catch container means, prior to the separation and discharge of the relatively larger marine items. This additional expansion chamber means is operable to
Another independently significant aspect of the invention involves the separating of relatively larger marine items from a flow of marine items flowing generally towards the marine-catch container means, and the discharging of such separated generally larger marine items generally transversely of the marine-catch container, means. In this aspect, this separating and discharging of said relatively larger marine items is operable to
Such separating is effected by flowing marine items toward a series of transversely extending, generally smooth, parallel, and straight rod surfaces which are operable to
These rod surfaces are substantially free of connecting surfaces on the upstream sides thereof and smoothly curve in a downstream direction at the outer extremeties thereof.
In the practice of this invention aspect, generally freely yieldable wall means serve to yieldably impede the discharging of marine items. Such wall means comprise
Having generally summarized independently significant aspects of the invention, it is now appropriate to describe prototype embodiments of the invention.
In thus describing the invention, reference will be made to appended drawings which illustrate, by way of example but not by way of limitation, two prototype embodiments of the invention, the first of which is presently preferred.